E
F. C. Demidoff et al.
Paper
Synthesis
Stilbene-Quinones 3a–l; General Procedure
HRMS: m/z [M + Na]+ calcd for C19H14O5Na: 345.073344; found:
345.0741.
A mixture of 3-iodolawsone (4; 300 mg, 1 mmol), styrene 5 (1 mmol),
NaOH (120 mg, 3 mmol), and Pd(OAc)2 (23 mg, 10 mol%) in PEG-400
(8 g) was stirred for 15 min at 90 °C. The reaction was monitored by
TLC. After this time, the reaction mixture was extracted with EtOAc
(50 mL) and filtered over a Celite pad. Then, 25% H3PO4 (50 mL) was
added. The organic layer was washed with brine (3 × 50 mL), dried
(Na2SO4), and concentrated in vacuum. The resulting oil was purified
by chromatography over silica gel (EtOAc/n-hexane; 5:95 for 3a–g
and 3k; 10:90 for 3l; and 30:70 for 3h–i) furnishing the desired pure
product.
(E)-2-Hydroxy-3-(3-hydroxy-4-methoxystyryl)naphthalene-1,4-
dione (3e)
Reddish-purple solid; yield: 65.1 mg (20%); mp 178–179 °C.
1H NMR (400 MHz, CD3OD): δ = 8.15–7.98 (m, 2 H), 7.85 (d, J = 16.7
Hz, 1 H), 7.82–7.70 (m, 2 H), 7.22 (d, J = 16.6 Hz, 1 H), 7.06 (d, J = 2.0
Hz, 1 H), 6.98 (dd, J = 8.3, 2.0 Hz, 1 H), 6.92 (d, J = 8.3 Hz, 1 H), 3.88 (s,
3 H).
13C NMR (101 MHz, DMSO-d6): δ = 184.99, 181.59, 159.89, 154.45,
148.82, 147.20, 134.78, 133.52, 127.15, 126.83, 126.28, 125.76,
119.65, 111.39, 72.75, 70.18, 60.66, 56.07, 55.98.
(E)-2-Hydroxy-3-styrylnaphthalene-1,4-dione (3a)17
Red amorphous solid; yield: 223.5 mg (81%); mp 160–161 °C.
HRMS: m/z [M – H] calcd for C19H13O5: 321.0768; found: 321.0782.
1H NMR (400 MHz, CDCl3): δ = 8.06 (d, J = 7.7 Hz, 1 H), 7.97 (d, J = 7.5
Hz, 1 H), 7.92 (s, 1 H), 7.85 (d, J = 16.7 Hz, 1 H), 7.65 (td, J = 7.6, 1.2 Hz,
1 H), 7.58 (td, J = 7.5, 1.2 Hz, 1 H), 7.49 (d, J = 7.4 Hz, 2 H), 7.28 (d, J =
16.8 Hz, 1 H), 7.32–7.24 (m, 2 H), 7.19 (m, 1 H).
13C NMR (101 MHz, CDCl3): δ = 184.12, 180.94, 151.68, 139.26,
137.75, 134.95, 133.18, 132.67, 129.52, 128.70, 128.69, 128.65,
127.17, 127.16, 127.12, 126.03, 118.66, 117.37.
(E)-2-[2-(Benzo[d][1,3]dioxol-5-yl)vinyl]-3-hydroxynaphthalene-
1,4-dione (3f)
Dark purple solid; yield: 53.4 mg (17%); mp 203–204 °C.
1H NMR (400 MHz, CD3OD): δ = 8.10 (dd, J = 7.5, 1.2 Hz, 1 H), 8.06 (dd,
J = 7.6, 1.3 Hz, 1 H), 7.90 (d, J = 16.6 Hz, 1 H), 7.81–7.71 (m, 2 H), 7.25
(d, J = 16.7 Hz, 1 H), 7.12 (d, J = 1.6 Hz, 1 H), 6.99 (dd, J = 8.0, 1.7 Hz, 1
H), 6.82 (d, J = 8.0 Hz, 1 H), 5.97 (s, 2 H).
LRMS: m/z = 276.
13C NMR (101 MHz, DMSO-d6): δ = 184.47, 180.89, 155.05, 148.48,
148.01, 136.46, 134.92, 133.74, 132.74, 132.43, 130.66, 126.47,
125.92, 122.45, 118.57, 117.09, 109.01, 105.65, 101.69.
(E)-2-Hydroxy-3-(4-methoxystyryl)naphthalene-1,4-dione (3b)14
Purple amorphous solid; yield: 70.3 mg (23%); mp 125–126 °C.
1H NMR (400 MHz, CDCl3): δ = 8.16 (dd, J = 7.6, 1.0 Hz, 1 H), 8.09 (dd,
J = 7.5, 1.1 Hz, 1 H), 7.94 (d, J = 16.7 Hz, 1 H), 7.76 (td, J = 7.5, 1.5 Hz, 1
H), 7.70 (td, J = 7.5, 1.4 Hz, 1 H), 7.56 (d, J = 8.5 Hz, 2 H), 7.27 (d, J =
16.7 Hz, 1 H), 6.92 (d, J = 8.8 Hz, 2 H), 3.85 (s, 3 H).
13C NMR (101 MHz, CDCl3): δ = 184.35, 180.85, 160.18, 151.16,
139.05, 134.81, 133.16, 132.71, 130.65, 129.62, 128.61, 128.60,
127.08, 125.96, 119.15, 115.25, 114.16, 114.15, 55.33.
HRMS: m/z [M – H] calcd for C19H11O5: 319.0612; found: 319.0622.
(E)-2-(2,3-Dimethoxystyryl)-3-hydroxynaphthalene-1,4-dione
(3g)
Red solid; yield: 106.1 mg (32%); mp 151–152 °C.
1H NMR (400 MHz, CDCl3): δ = 8.27 (d, J = 16.9 Hz, 1 H), 8.18 (dd, J =
7.6, 0.9 Hz, 1 H), 8.11 (t, J = 7.9 Hz, 1 H), 8.00 (s, 1 H), 7.76 (dd, J = 7.6,
1.4 Hz, 1 H), 7.71 (td, J = 7.6, 1.3 Hz, 1 H), 7.40 (d, J = 16.9 Hz, 1 H), 7.36
(dd, J = 8.0, 0.8 Hz, 1 H), 7.09 (t, J = 8.0 Hz, 1 H), 6.89 (dd, J = 8.1, 1.1 Hz,
1 H), 3.89 (s, 6 H).
13C NMR (101 MHz, CDCl3): δ = 184.14, 181.03, 153.04, 151.70,
147.50, 134.94, 133.67, 133.17, 132.68, 132.03, 129.55, 127.13,
126.03, 124.13, 118.98, 118.42, 112.34, 110.66, 61.26, 55.84.
HRMS: m/z [M + Na]+ calcd for C19H14O4Na: 329.0790; found:
329.0781.
(E)-2-Hydroxy-3-(4-hydroxystyryl)naphthalene-1,4-dione (3c)
Purple amorphous solid; yield: 58.4 mg (20%); mp 189–190 °C.
1H NMR (400 MHz, acetone-d6): δ = 8.17–8.02 (m, 2 H), 7.97 (d, J =
16.7 Hz, 1 H), 7.91–7.78 (m, 2 H), 7.50 (d, J = 8.5 Hz, 2 H), 7.28 (d, J =
16.6 Hz, 1 H), 6.90 (d, J = 8.6 Hz, 2 H).
HRMS: m/z [M – H] calcd for C20H15O5: 335.0925; found: 335.0912.
13C NMR (101 MHz, acetone-d6): δ = 184.15, 180.45, 158.10, 152.83,
137.88, 134.61, 134.49, 133.22, 133.07, 132.60, 130.29, 129.80,
128.35, 126.35, 125.47, 118.77, 115.68, 114.96.
HRMS: m/z [M + Na]+ calcd for C18H12O4Na: 315.062780; found:
315.0624.
(E)-2-Hydroxy-3-(4-nitrostyryl)naphthalene-1,4-dione (3h)
Prepared starting from 0.52 mmol of 5h; eluent for chromatography:
EtOAc/n-hexane (30:70); reddish-orange solid; yield: 163.8 mg (98%);
mp 153–154 °C.
1H NMR (400 MHz, acetone-d6): δ = 8.15–8.10 (m, 3 H), 8.08 (dd, J =
7.4, 1.1 Hz, 2 H), 8.04 (dd, J = 7.3, 1.3 Hz, 2 H), 7.89–7.84 (m, 3 H).
13C NMR (101 MHz, DMSO-d6): δ = 184.18, 181.67, 162.75, 156.80,
146.89, 144.85, 134.90, 133.91, 133.65, 130.71, 130.15, 127.83,
127.18, 126.89, 126.36, 125.82, 124.57, 111.41.
(E)-2-Hydroxy-3-(4-hydroxy-3-methoxystyryl)naphthalene-1,4-
dione (3d)
Reddish-purple amorphous solid; yield: 23.7 mg (7%); mp 186–
187 °C.
1H NMR (400 MHz, acetone-d6): δ = 8.10–8.02 (m, 2 H), 7.96 (d, J =
16.6 Hz, 1 H), 7.89–7.80 (m, 2 H), 7.28 (d, J = 16.6 Hz, 1 H), 7.25 (d, J =
1.9 Hz, 1 H), 7.10 (dd, J = 8.2, 1.6 Hz, 1 H), 6.88 (d, J = 8.2 Hz, 1 H), 3.95
(s, 3 H).
13C NMR (101 MHz, acetone-d6): δ = 184.58, 181.43, 158.38, 152.84,
147.79, 147.56, 138.09, 134.73, 133.06, 132.45, 130.17, 126.35,
125.92, 125.00, 120.91, 118.65, 115.06, 110.73, 55.25.
HRMS: m/z [M
– H] calcd for C18H10NO5: 320.056446; found:
320.0576.
(E)-2-Hydroxy-3-(2-nitrostyryl)naphthalene-1,4-dione (3i)14
Eluent for chromatography: EtOAc/n-hexane (30:70); reddish-orange
solid; yield: 279 mg (87%); mp 235 °C.
© Georg Thieme Verlag Stuttgart · New York — Synthesis 2017, 49, A–G